Fix GitHub Actions deployment workflow authentication

[bhouston]

GitHub Actions Deployment Workflow Failing

The deployment workflow (deploy-docs.yml) is failing because it's configured to use Workload Identity Federation (WIF) but the required secrets aren't available.

Current Configuration

The workflow is trying to use:

• ${{ secrets.WIF_PROVIDER }}
• ${{ secrets.WIF_SERVICE_ACCOUNT }}

Available Secrets

• GCP_SA_KEY - Appears to be a service account key

Proposed Solution

Update the workflow to use the service account key authentication method instead of Workload Identity Federation, or add the missing WIF secrets.

Option 1: Use Service Account Key

Replace the Google Auth step with:

- name: Google Auth
  id: auth
  uses: google-github-actions/auth@v2
  with:
    credentials_json: ${{ secrets.GCP_SA_KEY }}

Option 2: Add Missing WIF Secrets

Add the required WIF secrets to the repository:

• WIF_PROVIDER: The Workload Identity Provider ID
• WIF_SERVICE_ACCOUNT: The service account email to impersonate

Option 1 is quicker to implement but using Workload Identity Federation (Option 2) is Google's recommended approach for security.